Help Wtih Texture Controlled Particle Emission

I have a project I’m working on where I need to have particles look like they are emitting from a person running in some video.
I was able to pull a matte from the video with just the shape of the person so I have a black and white image of the silhouette running across the screen
(I have attached the image)

On the particles tab I can tell the particles to be emitted based on the texture, but this only seems to work for generated procedural textures. When I use my image from the video, it doesn’t work.

Any Ideas?
Thanks, in advance!


use this technique to accomplish the task
instead of importing the terragen stuff
import your person running
instead of the cube use particles